Metal-heating furnace



Oct. 28, 1930. R. KAIER METAL HEATING FURNACE Filed Aug. 3, 1927 5Sheets-Sheet l R. KAIER 1,779,435

'5 Sheets-Sheet 2 METAL HEATING FURNACE Filed Aug. 3', 1927 Oct. 28,1930.

DICE! Get. 28, 1930.

R. KAIER fi,7?9,435

METAL HEATING FURNACE Filed Aug. 5, 1927 5 Sheets-Sheet 5 Oct. 28 1930.R. KAIER METAL HEATING FURNACE Filed Aug. 3, 1927 SSheets-Sheet 4 Oct.'28, 1.930.

R. KAIER IETAL HEATING FURNACE Filed Aug. 3, 1927 5 Sheets-Sheet 5 I u It: H .HAu. EE w 9 5 3 EB Ban gwuentoc Patented Oct. 28, 1930 UNITEDRICHARD KAIER, 0F CRANFORD, NEW JERSEY, ilfitfillG-Iii NEW JERSEY, ll.UQIZM QHA'JIIQIQ" fill HEW {FIE-TEE TUBING COMPANY OF ELIZABETH,

METAL-HEATING FURNAGIEJ Application tiled August 3, 1927. Serial Mo.2165,?

This invention relates to metal heating furnaces and has for an objectto provide a furnace equipped with worlecarrying means for thecontinuous handling in quantities of small parts to be hardened by beingheated uniformly to a definite temperature and then quenched.

A further object of the invention is to provide for the handling of thework pieces without subjecting them to the danger of deformationheretofore caused by moving the parts relative to their supportingmeans.

To this end, the furnace preferably comprises an elongated heatingchamber with heavily insulated walls within which is supported a doubletrack-way having work-carrying and return runs between a loading stationat one end of the furnace and a clumping station at the other end of thefurnace. Supported by the track-way are two trains of flat, open-toppedwork-carriers or trays, one train being on the work-carrying run and theother being on the return run. The length of each train is onework-carrier length less than the lengthof the track-way, andcrossoverways are provided at the end of each run for transfer of theleading work-carrier to the other run. Suitable propelling means areprovided for laterally transferring the leading work-carriers along thecross-overs and for propelling each train of work-carriers along itsrespective run. Means are also provided for discharging the work fromeach work-carrier When it reaches the dumping station. The provision forreturn of the empty work-carriers within the furnace to the loadingstation conserves the heat of work-carriers and avoids the necessity ofre heating them. Thus the temperature of the work-carriers remainssubstantially constant at the furnace temperature and'the only heat lossis that which escapes with the quenching of the work plus the lnevitablelosses which latter-are reduced to a minimum by suitable insulation. Themaintenance of the work boxes at a constant temperature by keeping themsubstantially wholly within the heating chamber enables the furnacetemperature to be easily controlled within close limits, which would bedifiicult to do were the work boxes entirely removed from th lowed tocool more peratures.

In the accompanying drawing. is side elevation, partly in section, or afur"" embodying the invention. Fig. Q is verse side elevation of thefurnace. is a horizontal sectional view three furnace showing thework-carriers Fig. 4 shows the track-way for the r riers. Fig. 5 is asection on the in. a. Fig. 3. Fig. 6 is a section on the line Fig. 3.-Figs. 7, 8 and 9 are detail views of the worlccarrier tilting mac 10 isa section of the spe gear or diiferential shafts which pr el the 11 is aperspective view or o carriers. Fig. 12 is a shipper actuatii'wthrowing-in and Q speed drive, and Fig. la ing the relative tini' I forone complete rotation or. shafts.

In the preferred embed! tent of tion illustra l f bar in the form ofctangular box having side walls 9;, 3, end-walls 4t 5, a bottom wall 6and. a top wall 7, constructed of suitable refractoly material such asfire brick, and supported by legs 7. A series of gas-burners 8, directedinto the chamber 1 through the side walls thereof, supplies the as heatto maintain the chamber and its contents at the desired steady runningtem erature.

Supported on stilts 9 within the chamber 1 is .a work-carrier support10, prefer Y of some suitable heat-resisting alloy, such. as the wellknown nickel-chromium alloys: This support is in the form of arectangular plate having the longitudinal pairs of ridges 11, 12constituting longitudinal runs or traclc enama ways in SldG-bj U flfirelation between the as; loading station i cat/ed at A, Figs. 1 and 3,and the dumpir at the opposite ends of the fur Vs. sta ns and B thewortecarrier s pport mica crossover 1% ice Carried by the support is acomplement of work-carriers in the form of trays, each having an openedfront end 16, side walls 17, a rear wall 18 and downwardly extendingguide-lugs 19 which engage the inner sides of the several track-ways.The trays are arran ed in two trains, a work-carrier train C on t e run12 and areturn or empty train D on the run 11. The length of trains Cand D is one tray-length less than the distancebetween stations A and Bwhereby space is provided at the rear end of each train for the transferor cross-over of the leading tray of the other train. Train C ispropelled by the lever 20 which is-fulcrumed at 210m the bracket 21' andhas a cam-follower 22 entering the cam groove 23 in the cam-disk 24earned by the cam-shaft 25, which latter is journaled in the bearingbrackets 25 secured to the under side of the furnace. Train D ispropelled by the lever 26 which is fulcrumed at 27 on the bracket 27'and has a cam-follower 28 entering the cam-groove 29 in the cam-disk 30carried by the cam-shaft 31 journaled in the bearing brackets 31'. Whenthe leading tray of train 0 has been discharged of its contents, itispropelled over the cross-over at station B by means of the lever 32which is fulcrumed at 33, Fig. 6, and has its lower end connected by alink 34 to the cam-follower 35 at the lower end of the link 36 pivotedat 37 to the bracket 38. The cam-follower 35 enters the cam-groove 39 inthe cam 40 fixed to the shaft 31. The leading tray of train D ispropelled over the cross-over at station A by means of the lever 41fulcrumed at 42 on the bracket 43 and having a cam-follower 44 enteringthe cam-groove 45 in the barrelcam 46 fixed to the shaft 25.

The cam-shafts 25 and 31 are gear-connected to the shaft 47 which isjournaled in the bearing brackets 47 and drives the two camshafts intimed relation at the same speed. The drive-shaft 47 has fixed to it agear 48 with which meshes a worm 49 on the shaft 50 to which is keyedthe fixed pulley 51 driven by the belt 52 from the pulley 53 on thecounter-shaft 54 to which is fixed the pulley 55 iflrivezn by the belt56 from the motor-pul- It will be observed from Figs. 1, 3 and 5 thatone corner of the furnace is cut away at loading station A to expose thebeginning end of the trackway 12. When a work-carrying tray 15 is pushedalong the cross-over at A by the lever 41, it is momentarily exposed forreception of work-pieces which are placed therein by an attendant.

The discharge of the work-pieces from the carrier-trays is efl'ected bytilting each tray when it reaches the dumping station. To this end thereis mounted in a vertical slideway 58 in the bottom wall of the furnace,Fig. 7, a bar 59 the upper end of which enters the slot 60 in thetrack-way 10. The bar 59 is bifurcated at its lower end and carries across-pin 61 which passes through a slot 62 in one end of the lever 63fulcrumed at 64 on the bracket 65. The lever 63 carries a camfollower 66which is actuated by the cam 67 on the cross-shaft 31. The bar 59 is solocated that when it is lifted by action of the cam 67 on the lever 63it enga es and lifts the rear end of the leading tray 0 train C, therebytilting said tray, as shown in Fig. 1, and causing the work to slide outof such tray into the chute 68 which leads downwardly through theaperture 69 in the track-way 10 to the quenching tank 70.

To dislodge any work-pieces which may tend to stick to the tray, meansare provided for jarring such tray while in tilted position. Toaccomplish this there is mounted at the under side of the furnace abracket 71 in which is swiveled on pins 72 the fulcrum block 7 3 havingin it a slot 74 throu h which passes the lever 75 fulcrumed on t ecrosspin 76. The outer end of the lever 75 is connected by a link 77 tothe lever 78 fulcrumed at 79 on the bracket 80. The lever 78 bears uponthe cylinder 81 in the path of the tooth 82, which cylinder and toothare carried by the shaft 83 driven by a belt 84 from the pulley 53 onthe counter-shaft 54. A spring 85 pulling upwardly on the outer arm ofthe lever 75 restores such lever to horizontal position after eachactuation thereof by the link 77. A spring 86 tends to swing the lever75 to inoperative or dotted line position, Fig. 8, where it oscillatesidly under the action of the quick down pulls or jerks imparted to thelink 77 by the tooth 82.

After a tray has been tilted by lift of the bar 59, the lever 75 isswung from dotted to full line position, Fig. 8, wherein the inner endof the lever 75 extends under the bar 59 and imparts a series of upwardimpulses of comparatively small amplitude to the bar 59, thereby jarringthe tilted tray and effecting dislodgement of any work-pieces which mayhave stuck therein. The lever 75 is swung to operative position by theac tion of the cam 87 on the lateral pin 88 carried by the swivel-block73. The swivelblock 73 has a lateral swell 89 Fig. 8, which is adaptedto engage the bracket 71 and operate as a stop to limit the movement ofthe swivel block 73 and lever 75 under the influence of the spring 86.

The relative timing of the several cams is shown by Fig. 13 illustratingone complete cycle of movement or one complete rotation of thecam-shaft. The cross-feed of a tray at station A is first effected bythe cam 45 acting upon the lever 41. Upon return of the lever 41 toinitial position, the cross feed of a recently dumped tray at station Bfrom train C to train D is effected by the action of the cam 39 upon thelever 32. The tray fed to station A by lever 41 remains exposed at suchstation for a brief interval, say 2 or 3 seconds, for reception of aload of workpieces whereupon train C is advanced a traylength and therecently loaded tray is propelled into the furnace by the action of thecam 23 on the lever 20. As the lever 20 is returning to initial positionthe cam 29 acting upon the lever 26 is effecting the feed of empty trainD a tray-lengthQ The feed oftrain C carries its leading tray to thedumping station B and upon its arrival at such station the cam 67effects the lift of the bar 59 to tilt the tray. As soon as the tray istilted, the cam 87 swings the vertically oscillating lever under thelower end of the bar 59 to jar the tray. Upon the return of the lever 75to inoperative position, the cam 67 effects the lowering of the bar 59and the restoration of the tilted tray to its horizontal position. Theseveral actions are grouped to take place during a little more than halfof a revolution of the cam-shafts, there being no action during theremainder of the revolution.

In the particular machine described the time of one cycle is about 17seconds which multiplied by 8, the number of trays on run C, gives 136seconds or 2.26 minutes as the minimum time of passage of a workpiecethrough the furnace. To provide for an increase in the time of a cycleof any desired extent, to suit the character of the particular workbeing heated, there is mounted on the shaft 50, adjacent the fixedpulley 51 a differential pulley 90 onto which the belt 52 is shifted bythe belt-shipper slidebar 91 mounted in the bracket 92. The beltshipperbar 91 is actuated by the bellcranklever 93 which is rocked to-and-froby the cam blocks 94 which are clamped to the rim of the disk 95 fixedto the shaft 47. By shifting the cam-blocks 94 peripherally of the disk95, the slow drive may be started and stopped at any desired time in thecycle and the time of a cycle extended as desired. Preferably, the slowdrive is started and stopped during the portion of the cycle when thecams are not in action,

The differential pulley 90 is of standard construction. It is loose onthe shaft 50 and carries bearing-pins 96 for the connected pairs 97 ofgears of slightly different sizes. The inner gears mesh with a gear 98fixed to the shaft 50 while the outer gears mesh with a gear 99 on thehub of the ratchet 100 on which rests the pawl 101 having a fixed pivot102. When the belt is on the difi'eren tial pulley 90 the pawl 101prevents retrograde motion of the gear 99 and holds such gearstationary. When the belt is shifted to the fixed pulley 51 the gear 99and ratchet 100 are free to rotate at the higher speed.

While there is shown and described in detail one specific embodiment ofthe invention, it is to be understood that the invention is not limitedto the details of construction which may be variously modified by thoseskilled in the art within the spirit and scope of the invention.

Having thus set forth the nature of the invention, what I claim hereinis:

1. In a furnace, an elongated heating chamber having a work-receivingstation at one end and a work-discharging station at the other end, aseries of se arate work-carriers arranged in two si e-by-side trainswithin said heating chamber, one an outgoing work-carrying train and theother a return ,trainof empty work-carriers, means for discharging thework from the workcarriers and from the furnace at the discharging end,and means for transferring the work-carriers from the out-going train tothe return train. 1

2. In a furnace, a heating chamber having a work-discharging station, aseries of separate work-carriers with means for moving them within saidchamber to said work-discharging s'tation, tray-tilting means at thework-discharging station, and means for jarring said tray-tilting means.

3. In a furnace, a heating chamber, two side-by-side track-ways withinsaid chamber, cross-over ways at the opposite ends of said track-ways,trains of separate work-carriers on said track-ways, a pair of trainpropeller levers and a pair of cross-over propeller levers pivoted belowsaid chamber and having their free ends extending in the same directioninto the latter, and means for actuating said levers.

4. In a furnace, a heating chamber in the form of an elongatedrectangular box, parallel track-ways disposed lengthwise of and Withinsaid box, cross-overs at the ends of said track-ways, a complement ofwork-carriers carried by said track-ways, means for propelling saidcarriers, one corner of said box being cut away to expose one end of oneof said track-ways to form a work-receiving station, andwork-discharging means at the other end of said heating chamber.

5. In a furnace, a heating chamber in the form of an elongatedrectangular box, a pair of cam-shafts ournaled below and transversely ofsaid box adjacent the opposite ends of the latter, a shaft connecting.said camshafts in timed relation, means for driving said shafts, arectangular track-way within said chamber, a complement of separatework-carriers on said track-way, a plurality of work-carrier propellers,and cams on said cam-shafts for actuating said propellers.

6. In a furnace, a heatin chamber, a trackway in said chamber, wor-carriers on said track-way, means for periodically propelling saidcarriers to and past a discharge station, a work-carrier tilting barextending upwardly through the bottom wall of the furnace at thedischarge station within the track-way,

and means for reciprocating said bar between the periods of movement ofthe workcarrier propellers.

7. In a furnace, in combination, a movable hearth, means for causingsaid hearth to travel through the furnace, means for moving said hearthto cause the discharge of material therefrom, and means associated withsaid discharge means to cause the hearth to vibrate at the time ofdischarge.

8. in a furnace, a tiltable hearth, means for tilting said hearth, andbumping means associated with said tilting means for agitating saidhearth.

9. In a'furnace having a conveyor therein, a plurality of tiltablehearths mounted on said conveyor, means for periodically andsuccessively tilting said hearths, and means associated with saidtilting means for agitating said hearth.

10. In a furnace, the combination with a pivotally mounted hearth, andmeans for tilting said hearth, of means for causing jarring of hearthduring the tilting action.

in testimony whereofll have signed my name to this specification.

RICHARD KAIER.

